@startuml
set separator none
title Dynamic

top to bottom direction

skinparam {
  arrowFontSize 10
  defaultTextAlignment center
  wrapWidth 200
  maxMessageSize 100
}

hide stereotype

skinparam rectangle<<A>> {
  BackgroundColor #dddddd
  FontColor #000000
  BorderColor #9a9a9a
  shadowing false
}
skinparam rectangle<<B>> {
  BackgroundColor #dddddd
  FontColor #000000
  BorderColor #9a9a9a
  shadowing false
}

rectangle "Group 1" <<group1>> {
  skinparam RectangleBorderColor<<group1>> #cccccc
  skinparam RectangleFontColor<<group1>> #cccccc
  skinparam RectangleBorderStyle<<group1>> dashed

  rectangle "==A\n<size:10>[Software System]</size>" <<A>> as A
}

rectangle "Group 2" <<group2>> {
  skinparam RectangleBorderColor<<group2>> #cccccc
  skinparam RectangleFontColor<<group2>> #cccccc
  skinparam RectangleBorderStyle<<group2>> dashed

  rectangle "==B\n<size:10>[Software System]</size>" <<B>> as B
}

A .[#707070,thickness=2].> B : "<color:#707070>1. Uses"
@enduml